Fire protection system utilizing high-capacity direct discharge nozzles

ABSTRACT

A fire protection system wherein a source of extinguishant is connected to a plurality of high-capacity direct discharge nozzles mounted in an elevated position in the space to be protected. The nozzles are activated in a sequence dictated by their proximity to the fire, with the spacing between the nozzles and the configuration of the extinguishant discharge pattern from each nozzle being such that the operation of each nozzle is independent of the operation of the remaining nozzles. Each nozzle has the capacity to discharge the extinguishant at a rate of no less than one-eighth the total capacity of the system.

United States Patent Livingston 1 1 Oct. 17', 1972 [54] FIRE PROTECTION SYSTEM [56] 7 References Cited UTILIZING HIGH-CAPACITY DIRECT V UNITED STATES PATENTS DISCHARGE NOZZLES 2,298,061 10/1942 Lewis ..l69 /l6 Inventor: L. Sharon I t t t i t I Mass 3,388,747 6/1968 I-lodnetL. ..l69/42 X 3,454,097 7/1969 Groos ..l69/42 X [73] Assignee: Factory M ual Res r h Corp r 3,592,270 7/1971 Livingston ..l69/16 tion, Norwood, Mass. Y [22] Filed: Sept. 29, 1971 Primary Examiner-M. Henson Wood, Jr.

Appl. No.2 184,684

Related U.S. Application Data Continuation-impart of Ser. No. 72,333, Sept. 15, 1970, Pat. No. 3,653,444, which is a continuation-in-part ofSer. No. 864,612, Oct. 8, 1969, Pat. No. 3,653,444, which is a continuation-in-part of Ser. No. 885,501, Dec. 16, 1969, abandoned.

Int. Cl ..A62c 35/00 Field of Search ..169/5, 16, 42

V AW//)H7/// Assistant Examiner-Thomas Culp, Jr. Attorney-Joseph M. Lane et al.

[57] ABSTRACT A fire protection system wherein a source of extinguishant is connected to a plurality of high-capacity direct discharge nozzles mounted in an elevated position in the space to be protected. The nozzles are activated in a sequence dictated by their proximity to the fire, with the spacing, between the nozzles and the configuration of the extinguishant discharge pattern from each nozzle being such that the operation of each nozzle is independent of the operation of the remaining nozzles. Eachrnozzle has the capacity to discharge the extinguishant at a rate of no less than one-eighth the total capacity of the system.

7 Claims, 4 Drawing Figures PATENTEDnm 11 m2 SHEET 2 BF 2 INVENTOR WILLIAM L. LIVINGSTON ATTORNEYS FIRE PROTECTION SYSTEM UTILIZING IIIGII- CAPACITY DIRECT DISCHARGE NOZZLES CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of applicant s co-pending application Ser. No. 72,333 filed Sept. 15, 1970, now U.S. Pat. 3,653,444 which, in turn, is a continuation-in-part of applicant's co-pending applications Ser. No. 8 646l2filed on October 8, 1969, now US. Pat. No. 3,653,444 and Ser. No. 885501 filed on Dec. 16, 1969, Now abandoned. The disclosures of each of these applications are hereby incorporated by reference. I I

BACKGROUND OF THE INVENTION A This invention relates to a fire protection system, and more particularly, to such a system employing a plurality of high-capacity direct discharge nozzles mounted in an elevated position in the space to be protected from fire. g I A Fire protection systemsfor protecting industrial and commercial properties have traditionally employed thermal releasable sprinkler heads located in an elevated position with respect to the space to be protected. The sprinkler heads are supplied with a suitable extinguishant, such as water, by a pipe network of mains, risers, crossmains, and branch lines. Each head usually has a relatively small discharge opening, such as k inch in diameter, with their discharge capacity being between one-fortieth and one-twentieth of the total capacity'of the'system. Also, the heads are spaced a relatively short distance apart, such as 10 feet. On actuation of each head by collapse of a thermal responsive linkage, the extinguishant stream issuing from its discharge opening impinges against a serrated deflector disc to form a hemispherical pattern of droplets simulating the characteristics of rain. l

, Although I automatic sprinkler systems employing these type heads have been an effective meansfor the protection of property against loss or damaged by fire, the trend during recent years to high storage enclosures, coupled with the increased use of plasticsand other highly flammable materials, has presented new challenges for such systems. For example, recent extensive studies with actual and synthetically produced fire plumes have shown that in enclosed spaces of feet and higher, the updraft or chimney effect caused by convection alone is sufficient to prevent the free-falling water droplets produced by sprinkler heads from penetrating therising fire plume and reaching the burning fuel surfaces. Therefore, these heads, with their above-mentioned low-capacity discharges, often are unable to effect a sufficient penetration to the rising fire plume to aid in effective prevention of the spread of same.

Although attempts have been made to compensate for the low capacities of these beads by increasing the number of heads and decreasing the spacing between the heads, several problems developed. First of all, such an increase in the number of heads is expensive. Secondly, a portion of thehemispherical discharge pattern from the heads has a radial component which, in

the proper circumstances, would impinge against and inhibit the actuation of its adjacent head. Thus some heads located directly above he fire would often not be actuated until some more remotely located heads are actuated.

2. Further, the heat ofa localized high-challenge fire would often actuate numerous heads located ata great distance from the fire which would be ineffective to deliver water or other extinguishant directly to the fire. This contributed not only to redundant and flooding use of water, but also robbed water from the heads located directly over the fire. e 3

SUMMARI OF THE INVENTION It is therefore an object of the present'invention to utilize a system employing a plurality of direct discharge nozzles having a. relatively high-capacity discharge rate and to limit-thenumber of the nozzles nozzle from affectingthe operation of oneor more of the other nozzles. As a result, the nozzles are activated in a logical sequence and the relatively high velocity discharge of the relatively large quantity of water has a good chance of effectively penetrating the fire plume to an extent that the fire plume is knocked down and the fire extinguished at its early stages of development.

Toward the fulfillment of this and other objects, the system of the present invention comprises a source of extinguishant, a plurality'of direct discharge nozzles mounted in an elevated position in the space to be protected, means connecting said source of extinguishant to said 'nozzles, and means responsive to information received from a fire occuring in said space for selectively actuating said nozzles in a sequence dictatedby each nozzles proximity'to the fire..The spacing between the nozzles and the configuration of the extinguishant discharge pattern from each nozzle is such as to render the operation of each nozzle independent of' the operation of the remaining nozzles, with each nozzle having the capacity to discharge the extinguishant at a rate of no less than one-eighth the total capacity of the system.

BRIEF DESCRIPTION OF THE DRAWINGS the system of the present invention;

FIG. 3 is a vertical sectional view of a direct discharge nozzle employed in the system of FIGS. 1 and 2; and

FIG. 4 is an-enlarged partial view of the nozzle of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS for delivering the extinguishant, in this case water, to a riser 18. The riser 18 is connected to a cross main 20 which, in turn, is connected to a plurality of branch lines 22 via couplings 24. As better shown in FIG. 2, the cross main 20 and the branch lines 22 are suspended near the ceiling 26 of the building in a conventional manner.

Each branch line 22 has a plurality of nipples 28 depending downwardly therefrom with a nozzle 30 being attached to each nipple. The buried feed main 14 extends beyond the riser 18 and can be connected to risers of other buildings or, in the case of a large building, to other risers in the same building.

In accordance with the present invention, the nozzles 30 are in the form of direct discharge nozzles each of which is designed to discharge the water at a rate of no less than approximately one-eighth the total capacity of the system, with the nozzles being spaced apart relatively great distances when compared to nozzles and sprinkler heads of prior art systems. In accordance with a preferred embodiment and assuming a floor to ceiling height of about thirty feet, the nozzles 30 on each branch line 22 are spaced about fifteen feet apart and are staggered relative to the nozzles on the adjacent lines, the spacing between branch lines is about 15 feet, and each nozzle is designed to discharge the water at a rate of between one-fifth and one-third of the total capacity of the system.

As an example of the latter, and assuming a pressure supplied by the municipal water main 16 of 40 to 50 pounds per square inch, the system of the present invention would be designed to provide a minimum flow through the riser 18 of 550 gallons per minute and a maximum flow of 750 gallons per minute in which case each nozzle 30 would be designed to discharge the water at a rate of no less than 93 gallons per minute and preferably at a rate of between 150 gallons per minute and 250 gallons per minute. With this in mind the riser 18, in accordance with the present invention, would employ 4 to 5 inch piping and the branch lines 22 would employ 2 to 3 inch piping. The outlet orifice of each of the nozzles 30 would be about 1% inches to 1% inches in diameter.

As a specific example of a system which realizes the above characteristics, the riser 18 is made of 4 1% inch piping, the cross main 20 is made of 3 1% inch piping, the branch lines 22 are made of 2 kinch piping, and the outlet orifice of each of the nozzles is l inches in diameter providing a maximum discharge rate of approximately 200 gallons per minute.

As shown in FIG. 2, a plurality of stacks of combustible materials or fuel piles, designated by the reference letters A-F, represent the type and arrangement of materials typically stored in the building 10. The nozzles 30 are adapted to deliver a divergent, downwardly directed spray of water droplets towards the fuel piles, with the spray patterns from the adjacent nozzles taking the general form shown, it being noted that the discharge from each nozzle does not impinge upon, or otherwise interfere with the operation of its adjacent nozzles. The nozzles 30 are adapted to be actuated automatically, i.e., each nozzlewill be-normally closed but will be opened in a sequence dictated by its proximity to the fire, as will be explained in detail later.

The details of a nozzle 30 are shown in FIG. 3. In particular, the nozzle 30 comprises a cylindrical body 32 having an upper end portion which is internally threaded as shown at 34 for connection to a source of extinguishant, such as water, and a lower end portion which defines an outlet orifice 36 of a reduced crosssection. A pair of spiral vanes 38a and 38b are fixed within the body 32 for imparting a swirling motion to the waterflowing downwardly therethrough in a conventional manner. The vanes 38a and 38b support a hollow central hub 40 which, in turn, slidably supports a rod 42 having a plug member 44 fixed on its lower end and extending in the outlet orifice 36. A pair of sealing rings 46 and 48 are positioned about the periphery of the plug member 44 and sealingly engage the inner wall of the body 32 near the outlet orifice 36.

The rod 42 is latched in the position shown in FIG. 3 by a rod 52 which extends slidably through an externally threaded boss 54 projecting from the side of the body 32. One end of the rod extends through the vane 38a and the wall of the central hub 40 into a slot 56 in the rod 42 to latch it in the position shown in FIG. 3.

A sleeve 58 is threaded on the end of the boss 54. The outer end of the sleeve is closed off by an externally threaded stub shaft 60 having a ring or yoke'62 thereon. The rod 52 slidably extends through the stub shaft 60 and the other end of the rod engages a conventional thermal fuse element 64 positioned within the ring 62. The fuse element 64 prevents movement of the rod 52 the right as viewed in FIG. 5, until the heat of a fire fuses the element 64 so that it collapses. Since the fuse element 64 is the standard type commonly used in conventionalsprinkler heads now on the market, it will not be described in greater detail.

The rod has a piston head 66 mounted thereon which slidably engages the internal wall of the sleeve 58. A spring 68 is positioned between the boss 54 and the piston head 66 to bias the piston head and the rod 52 to the right with a predetermined biasing force.

With this arrangement, the piston head 66 and the rod 52 will be driven to the right under the action of the spring 68 upon the fuse element 64 collapsing in response to the heat of the fire, which unlatches the rod 42.

A detent mechanism is provided for preventing expulsion of the rod 42, and therefore the plug member 44, despite release of the fuse element 64 in the event the water pressure in the body member 32 is below a predetermined value. This detent mechanism is better depicted in FIG. 4, and comprises a sleeve 76 disposed on the upper portion of the upper vane 38a and having a reduced portion 76a which extends into a counterbore formed in the upper end portion of the hub 40. A

, set screw 78 extends through the latter upper end portion and engages the reduced portion 76a of the sleeve 76 to fix the latter in a concentric position within the hub 40 The hollow portion of the sleeve 76 receives the upper end portion of the rod with a slight clearance being provided to permit movement of the rod relative to the sleeve.

intervals, and since the balls and their supporting structure are identical, only one is shownand described in detail for the convenience of presentation.

In particular, the ball 80 is supported in one end of a radial bore 82 formed through the sleeve 76, and a v compression spring 84 is disposed in the bore 82 and urges the ball outwardly from the end of the bore, with a tapered shoulder 82a being formed at the end of the bore to prevent complete discharge of the ball fromthe bore. A plug86 has a portion extending in the other end of the bore 82 in engagement with the spring 84 and engages the walls of the bore with a frictional fit so that its position in the bore can be adjusted in order to vary the compressive load on the spring. One end portion of the plug 86 projects from the end of the bore 82 and is of a generally round shape, and a pin 88 extends from the other end portion of the plug 86 and receives the spring 84 to center the latter in the bore 82.

A continuous groove 89 is formed around the circumference of the rod 42 near the upper end thereof in alignment with the ball 80. In this manner, the spring 84 urges a portion of the ball 80 into the groove 89 to lock the rod relative 42 to the body member 32, with the magnitude of the locking force being determined by the position of the plug 86 in the bore 82 and the resultant compression of the spring 84.

A cap 90 extends over the sleeve 76 and has an externally threaded plug portion 92 which engages corresponding threads formed in the upper portion of the bore in the sleeve 76. The internal wall of the cap 90 has a tapered inner surface 94 which engages the plug 86. As a result, rotation of the cap 90 will cause it to move axially relative to the sleeve 76 and cause a corresponding variation in the amount of camming force applied to the plug 86 by the tapered inner surface 94.

This, in turn, regulates the load on the spring 84, the

locking force applied to the rod 42 by the ball 80, and therefore the amount of minimum static water pressure in the body member 32 required to release the rod 42.

Since the sleeve 76 and the cap 90 are both concentrically aligned relative to the rod 42, the load on each ball can be regulated to an exact degree in order to precisely adjust the amount of force required to release the rod 42 and therefore the plug member 44 from the detent mechanism.

This minimum pressure required to actuate said nozzle 30 can vary according to the particular requirements of the system. As an example, and assuming the line pressure provided by the municipal water main is approximately 40 pounds per square inch and that it is determined that the highest challenge fire for the building will normally not cover an area greater than the area of responsibility for seven nozzles 30, a minimum pressure of approximately 10 pounds per square inch will be selected for each nozzle.

If the fuse element 64 of a particular nozzle 30 is thermally actuated in response to an elevated temperature in their vicinity, the tension of the spring 68 causes the rod 52 to release the rod 42. The water pressure in the body member 32 acting on the inner end face of the plug member 44 forces it downwardly as viewed in FIG.

3, in direct proportion to the amount of pressure. If the force acting on the plug member 44 as a result of thispressure exceeds the locking force applied to the'rod 42 by the spring-loaded balls 80, the rod 42 will be released, and it, along with the plug member 44, will discharge outwardly from the body member 32 under the force of the water pressure. Of course, if the extinguishant pressure is not sufficient to overcome the locking force provided by the spring-loaded balls 80, the plug member 44 will not be expelled from the body portion 32 despite the release of the fuse element 64.

With this arrangement, and assuming the specific exemplary design parameters set forth above, the first nozzle 30 to be thermally actuated by virtue of the fusing of its link 64 due to the heat of a fire will be insured of being opened due to the existance of the 40 pounds detent mechanism and permit expulsion of the plug member 44. This nozzle will discharge the water at its maximum rate of 200 gallons per minute and will alone have a good chance of extinguishing the tire because of the increased ability of the larger droplets discharged therefrom to penetrate the tire plume. If the heat of the fire spreads, a second nozzle 30, very probably adjacent the first actuated nozzle discussed above, will be thermally actuated and will have a slightly decreased pressure available to it, but much larger than the 10 pounds per square inch minimum pressure required to open it. Therefore, the plug member 44 from the latter nozzle will be expelled and water will also be discharged from the nozzle at the maximum rate of 200 gallons per minute.

In the event the fire continues to spread, the nozzles 30 will continue to be opened in a logical sequence dictated by their proximity to the tire especially since the operation of each nozzle is not influenced by the discharge pattern from any other nozzle. This continues until the design limit of seven nozzlesis reached,

at which time the detent mechanism of additional nozinclude cost savings since, due to the relatively large spacing between the nozzles, the number of nozzles as well as the associated branch lines etc., are reduced. Also, despite the relatively large discharge rate for such nozzle, the total water' requirement for the system is relatively low, due to the fact that the number of nozzles to be actuated are limited. Further, the relatively act arrangements, which will often knock down the fire plume at its early stages of development.

Several variations can be made in the foregoing without departing from the scope of the invention. For example, each nozzle or all the nozzles along each branch line can be adapted to be actuated in response to a different minimum extinguishant'pressure depending on their distance from the riser 18, in order to compensate for friction losses in the system.

Also, other means may be provided to effect the above-mentioned minimum actuation pressure.

Of course, still other variations of the specific construction and arrangement of the fire protection system utilizing high-capacity direct discharge nozzles disclosed above can be made by those skilled in the art without departing from the invention as defined in the appended claims.

I claim I l. A fire protection system comprising a source of extinguishant, a plurality of direct discharge nozzles mounted in an elevated position in the space to be protected, means connecting said source of extinguishant system.

2. The system' of claim 1 wherein each nozzle has an outlet orifice of approximately 1 inches in diameter.

3. The system of claim 1 further comprising means responsive to a predetermined condition of said system for preventing the discharge of extinguishant from said nozzles despite said actuation of said nozzles. I

4. The system of claim 1 further comprising means responsive to the absence of -a predetermined extinguishant pressure at each of said nozzles for preventing the discharge of extinguishant from said nozzle despite said actuation of said nozzle.

5. The system of claim 1 wherein each nozzle has the capacity to discharge the extinguishan t at a rate of between one-fifth to one-third the total capacity of the system.

6. The system of claim 1 wherein each nozzle has the capacity to discharge the extinguishant at a rate of between and 200 gallons per minute.

7. The system of claim 1 wherein said means responsive to information received from the fire is responsive to the temperature in the immediate vicinity of each of said nozzles.

2 33 T UNITED STATES PATENT OFFICE CERTEFICATE OF CORRECTION Patent No. 3, ,4 2 Dated nm-nhpr 17 m7? Inv ntor(s) L- LiVingStOn It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the face of the printed patent, under the heading Related U.S. Application Data, line .4, "Pat. No. 3, 653, 444" should read Pat. No. 3,645, 338-.

Column 1, line 9 "U.S. Pat. No. 3 653,444" should read --U.S; Pat. No. 3,645,338-.

Column 1, line 10 "Now abandoned. should read now abandoned.

Column 1, line 65, "above he" should read above the--.

Column 2, line 56, "View of the" should read view of a.

Column 2, line 50 delete "bu ilding" (first occurrence) Signed and sealed this 10th day of April 1973.

(SEAL) Attest:

EDWARD M.PLETCHER,JR. ROBERT GOTTSCHALK A t'tes'ting Officer Commissioner of Patents 

1. A fire protection system comprising a source of extinguishant, a plurality of direct discharge nozzles mounted in an elevated position in the space to be protected, means connecting said source of extinguishant to said nozzles, and means responsive to information received from a fire occuring in said space for selectively actuating said nozzles in a sequence dictated by each nozzle''s proximity to the fire, the spacing between nozzles and the configuration of the extinguishant discharge pattern from each nozzle being independent of the operation of the remaining nozzles, each nozzle having the capacity to discharge the extinguishant at a rate of no less than one-eighth the total capacity of the system.
 2. The system of claim 1 wherein each nozzle has an outlet orifice of approximately 1 3/8 inches in diameter.
 3. The system of claim 1 further comprising means responsive to a predetermined condition of said system for preventing the discharge of extinguishant from said nozzles despite said actuation of said nozzles.
 4. The system of claim 1 further comprising means responsive to the absence of a predetermined extinguishant pressure at each of said nozzles for preventing the discharge of extinguishant from said nozzle despite said actuation of said nozzle.
 5. The system of claim 1 wherein each nozzle has the capacity to discharge the extinguishant at a rate of between one-fifth to one-third the total capacity of the system.
 6. The system of claim 1 wherein each nozzle has the capacity to discharge the extinguishant at a rate of between 150 and 200 gallons per minute.
 7. The system of claim 1 wherein said means responsive to information received from the fire is responsive to the temperature in the immediate vicinity of each of said nozzles. 